1. Field of the Invention
This invention relates to improvements in a filter. More particularly, the present filter can automatically expands to provide new filter surface area to maintain uniform static pressure. The filter can be provided in square or round configurations.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98.
Filters are used in a variety of places including but not limited to HVAC units, vacuums, automobiles and other places. For most or all of the filters used in these applications the installed filter has a fixed amount of filter surface area. As the filter gets clogged the efficiency of the apparatus has to work harder to pull air through the filter and will stop filtering completely if no warning is in place. A number of patents and or publications have been made to address filter applications. Exemplary examples of patents and or publication that try to address this/these problem(s) are identified and discussed below.
U.S. Pat. No. 6,740,137 that issued on May 25, 2004 to James O. Kubakawa et al discloses a Collapsible Pleated Filter Element. The pleated filter element collapses as the pleats fold upon each other. While the high and low peaks and valleys provide for additional surface area that is not present in a flat filter, once the filter is placed within the filter holder the surface area of the filter remains unchanged.
U.S. Pat. No. 5,968,217 issued on Oct. 19, 1999 to Myron Stein et al, and U.S. Pat. No. 7,037,354 that issued on May 2, 2006 to Anthony Dimicelli both disclose expandable air filter systems. The expandable air filter systems are essentially an expandable filter mounted within an expandable frame. These patents allow for a frame to be compressed and set within a forced air unit and then expanded accommodating the required filter size. This type of product is particularly useful when the actual dimensions are not known. While the filter may be expandable upon installation, once the filter is installed the filtering surface area remains unchanged as the filter collects debris.
U.S. Pat. No. 6,152,980 issued on Nov. 28, 2000 to C. William Culwell discloses a size adjustable filter element. A pleated filter element is slid into a “C” frame with multiple metal reinforcing members. Once the filter element is installed the pleated filter is expanded to fill a plenum cross section. While this filter is expandable, the filter surface area does not change or adjust as the filer becomes clogged thereby allowing the pressure or vacuum to change as the filter clogs.
The waste particles that are released into the atmosphere from brake pads also creates multiple dilemmas. As force is applied to brake pads, the material on the pads is ground away. This material is known as brake dust and can be problematic for two main reasons. The first is that brake dust is highly corrosive and harmful to the environment. It is estimated that up to ninety percent of the worn away brake pad particles are released into the atmosphere. The dust particles created, which contains copper, brass, Kevlar, carbon fibers, metal filings, asbestos to name a few and acidic adhesive material, is extremely caustic to the environment. The second problem is that the remainder of the brake dust particles that are not released into the atmosphere is deposited on the vehicle wheels. The brake dust particles can be corrosive enough to burn through wheel coatings and leave expensive wheels damaged and unsightly. As a result, there have been a number of devices that have introduced dust shields or filter systems designed to reduce brake dust. These include U.S. Pat. Nos. 7,094,268, 4,484,667, 6,371,569, 6,173,821, 6,932,199, 6,155,650 and 5,772,286. U.S. Pat. No. 5,162,053 discloses a system that utilizes a suction mechanism along with a filter to capture brake dust. Finally, U.S. Pat. No. 6,592,642 discloses a device that utilizes an electrostatic charge to collect charged brake dust particles.
What is needed is filter that self-adjust in size to provide new filter material as the pressure or vacuum in changes. The proposed application provides a solution with a filter that in initially installed in a collapsed configuration with a first surface area of filter material. As the first filter surface area becomes clogged, the change in pressure or vacuum causes the filter to expand and expose a larger surface area of filter material.